By Saman Dharmakeerthi
The cupboard of Sri Lanka on the 29thApril, 2021 has authorised a ban on importation of chemical fertilizers and different agrochemicals within the bid to turn into the primary nation ever to follow natural solely agriculture. The coverage doc of the current authorities,“Vistas of Prosperity and Splendour”,which has been mandated by the practically 2/3rd of the voters on the 2018 Presidential Election, state that Sri Lankan agriculture will promote and popularize natural agriculture throughout subsequent ten years. Their intention is to guard the well being of the folks and surroundings of the nation which have been deteriorated on account of agrochemicals utilized in standard agriculture.
The Authorities claims that due to chemical fertilizer utilization, soil fertility has been degraded, soil acidity elevated, biodiversity diminished, and most of all,yield and yield high quality has additionally not been improved. The Authorities additionally claims that chemical fertilizer utilization has resulted water air pollution andaccumulated poisons in meals,resultinggreater incidence of most cancers andchronic kidney illness (CKDu) in Sri Lanka. Whereas this author agrees that chemical nitrogen fertilizer may result in soil acidification, different points said above are widespread to each natural and inorganic fertilizers,in by hook or by crook, if poor high quality fertilizers are utilized towards the suggestions made by Crop Analysis Institutes. The argument that chemical fertilizers haven’t elevated crop yields in a given soil crop-environment can’t be justified both. Due to this fact, this writeris nonetheless making an attempt to know the opposite causes for banning chemical fertilizers in Sri Lanka.
The natural motion began within the 20thcentury in German- and English-speaking nations, and was influenced by completely different teams that promoted rural traditions and using organic (as a substitute of artificial) fertilizers. It has gained reputation because the Seventies with rising public considerations about well being and environmental results of “industrialized” farming.After the inexperienced revolution of Dr Norman Borlaug and Dr M.S. Swaminathan within the 1960’s, agriculture used crop varieties which can be attentive to available nutrient sources. Even in Sri Lanka, plant breeders produced varieties that weremore attentive to nutrient inputs. Due to this fact, using chemical fertilizers turned inevitable to realize increased yields even todate. As a result of a number of causes that are past the dialogue of this text, farmers apply chemical fertilizers indiscriminately of their agricultural fields ensuing many environmental and well being points. So as to add salt to the wound, the standard of some chemical fertilizers out there available in the market doesn’t meet minimal requirements. Improper utilization and poor high quality of chemical fertilizers has due to this fact raised considerations amongenvironmentalists and politicians. Therefore,the current authorities is making an attempt to advertise various applied sciences which can be solely natural. Division of Agriculture has already suggest variety of applied sciences, reminiscent of precision farming and promote the appliance of natural fertilizers, to will increase the soil fertility and effectivity of added plant vitamins.
The scientific neighborhood is split on whether or not natural agriculture may feed the world or not. In Could 2007 on the FAO Convention on Natural Agriculture, Dr. Badgely and associates contributed to the controversy by presenting an evaluation supporting the concept that natural agriculturecan significantlyincrease productiveness in growing nations andcould feed the whole world. This paper has obtained a lot consideration within the well-liked press and science magazines such because the New Scientist. Nonetheless, within the following 12 months,Dr. Nook identified that Dr Badgely’s findings wereinvalid as a result of information weremisinterpreted and calculationsaccordingly wereerroneous. In a latest publication which appeared inthe Annual Evaluate of Useful resource Economics, Meemken and Qaim reviewed and analyzed the in depth literature on numerous facets of natural farming, together with manufacturing, social well-being, surroundings, and economics. They concluded that natural farming is just not the paradigm for sustainable agriculture and meals safety, however sensible mixtures of natural and traditional strategies may contribute in direction of sustainable productiveness will increase in international agriculture.
Encouraging additional deforestation
Individuals who promote natural agriculture guarantee that land productiveness won’t be affected in the long term or may typically be even increased than that of standard agricultural methods. Three scientifically extra rigorous meta-analyses of organic-conventional crop yield comparisons had been printed in the previous couple of years. Outcomes of those analyses clearly signifies that throughout all crops, imply yield reductionin natural agriculture are within the magnitude of 19–25%. Appreciable variations will be noticed throughout completely different crop species, with legumes and fruits displaying smaller yield gaps than cereals and root and tuber crops. If that’s the case, with the intention to feed the rising inhabitants extra lands must be cleared and introduced into agriculture. For an instance, discount of paddy yields by mere 20% should improve the conversion of about 33,000hectares of extra lands in to paddy cultivation despite the fact that we produce about 0.5 million tons of rice over the self-sufficiency degree. In an period the place applied sciences must be invented and launched to extend the productiveness of lands with the intention to guarantee the meals safety of the nation, natural agriculture with out correct technological recommendation for farmers and policymakers may result in additional deforestation sooner or later.
Availability of natural fertilizers
To produce the crop nutrient demand, an infinite amount of natural fertilizers and biofertilizers should be produced inside the nation.Presently, about 3500 tons of municipal natural wastes are generated per day within the countryand from that, about 2-3 million tons of compost may very well be produced per 12 months. Nonetheless, for natural paddy cultivation alone it requires practically 4 million tons of compost at a really nominal charge of 5 tons per hectare. For tea plantations,this determine may very well be effectively over one other 3 million tons. Nonetheless, at current the nation is producing solely 0.22 million tons of compost by way of each Division of Agriculture registered producers and by municipal councils. Therefore there’s a humongous process forward to supply natural fertilizers within the nation. We can’t advocate the importation of natural fertilizers at any price if we’re to safeguard our folks and the surroundings.
Misconceptions on natural agriculture
With all that drawbacks in adopting and implementing natural solely agriculture, this author additionally believes that the proper utilization of natural fertilizers has the sting over chemical fertilizers in environmental standpoint. Nonetheless, environmental advantages alone can’t obtain sustainability in agri-food methods. Among the many individuals who advocate organic-only agriculture, there are some misconceptions that should be pointed, after which talk about and debated for the better- and well-informed determination making by policymakers.
False impression 1. Chemical fertilizers are chargeable for well being and environmental considerations in Sri Lankan agriculture: Among the well being and environmental considerations associated to the chemical fertilizer utilization usually are not supported by scientific proof. A very powerful instance associated to that is the incidences of continual kidney illness of unknown etiology (CKDu) that’s prevalent amongst farmers within the Dry Zone. This has been associated to cadmium and arsenic current in Triple Tremendous Phosphate (TSP) importedinto Sri Lanka. Although cadmium and arsenic have been present in extra concentrations in fertilizers out there within the native market, to this point, noscientific proof has been publishedto show past cheap doubt, that heavy metals in TSP (or every other chemical fertilizer) is linked to CKDu prevalence in Sri Lanka. Current scientific proof confirms that bioavailable, doubtlessly poisonous hint steel concentrations in agricultural soils and in ingesting waters are effectively under the EU outlined most permissible ranges. Cyanotoxins, fluorides and hardness in effectively water have been shortlisted as doable causes in line with an article printed within the Nature Scientific Studies.
The opposite well being difficulty that raises concern is the carcinogenicity of greens which have excessive focus of nitrates. Accumulation of nitrate in leafy greens at excessive ranges is a risk if nitrogen fertilizers are utilized in “extreme” portions. Including beneficial charges of N fertilizer present solely a minimal risk for accumulation of N in crops.We now have noticed extraordinarily excessive phosphorus concentrations in intensively cultivated vegetable fields within the upcountry however there isn’t any fast well being difficulty associated to phosphorus, besides the potential of cyanotoxin producing micro organism proliferation on account of excessive concentrations of phosphorus in water. There’s a main environmental difficulty associated to extraordinarily excessive P in agricultural soils because it may set off eutrophication in floor water our bodies. Excessive P in agricultural soil is because of extra P software, non-availability of P free fertilizer combination and software of poultry manure. Potassium and Magnesium containing fertilizers are comparatively much less dangerous.
Shut have a look at the causes of points associated to chemical fertilizers; one may discover that it’s primarily as a result of poor high quality of the imported fertilizers and their incorrect utilization. Fertilizer importers are largely chargeable for importing fertilizers containing heavy metals into the nation along with officers who regulate fertilizer importation. I don’t level fingers at farmers for indiscriminate fertilizer software, as a result of firstly, it’s only some business agriculture practising farmers who apply excessive charges of fertilizers as an insurance coverage dose and even they do it as a result of fertilizers are freely out there at backed costs. Secondly, they’re typically ignorant about acute environmental penalties associated to unhealthy nutrient administration practices.
False impression 2. Natural solely nutrient administration applied sciences are all the time environmentally pleasant: That is one other large false impression and people who advocate environmental security and human well being have typically missed or purposely ignored some detrimental externalities associated to natural farming. Assume anintensively cultivated vegetable cropping system in Nuwara Eliya the place very excessive ranges of Phosphorous are current in soil. Because the most limiting nutrient is N, giant portions of natural fertilizers must be utilized. If a minimal of 5000kg of compost,which comprises 2% N and 0.5% phosphorus, is utilized to fulfill the N requirement, a farmer might be making use of 25 kg of phosphorus each season when environmentalists shout to not apply phosphorus into such lands. Poor farmers can’t change the composition of natural fertilizer out there available in the market or they produce and contribute to the acceleration of eutrophication and cyanotoxicity because of ill-advised natural farming.
Poultry litter is without doubt one of the mostly out there natural fertilizer supply, subsequent to compost. They containchicken manure that’s wealthy in nitrogen and waste feed that comprises excessive phosphorus. Nonetheless, latest scientific proof confirms that there are antibiotic traces current in poultry manure and antibiotic resistance is being developed in soils amended with them. As well as, the standard of the uncooked supplies utilized in natural fertilizer manufacturing is essential to supply anenvironmentally protected natural fertilizer. In a growing nation like Sri Lanka the place the system could be very corrupt, when the uncooked supplies are depleted, business producers will resort to utilizing low-quality supplies reminiscent of sewage sludge, municipal strong waste which can be amply and freely out there for natural fertilizer manufacturing. Such uncooked supplies comprise doubtlessly poisonous hint metals and typically even pathogens and will end in even higher repercussions than what now we have now.
Due to this fact, high quality of the natural fertilizers and their appropriate utilization determines the environmental friendliness of natural farming. After we can’t even guarantee the standard of the chemical fertilizers imported and marketed within the nation, how can we set high quality requirements for an array of various fertilizers and regulate the standard of natural and bio-fertilizers? Don’t even consider importing natural or bio-fertilizers as, they will threaten bio-diversity of Sri Lankan soilon one hand. Then again,we can’t guarantee the standard of such fertilizers, and due to this fact any rubbish will be introduced in and dumped into our treasured pure useful resource: the soil. The presence of weed seeds, pathogens, poisonous heavy metals and natural pollution have to betested and for that high quality requirements must be formulated first.
False impression 3.Natural-fertilizer-only approaches can all the time maintain crop productiveness: Out of 18 important components required for optimum plant development,nitrogen, phosphorus, potassium and magnesium are poor inmost agricultural soilsin Sri Lanka. Nonetheless, some analysis findings means that the appliance of phosphorus fertilizer over lengthy intervals has elevated the plant out there P ranges, and crops are much less attentive to phosphorus fertilizers. Though a cropping system may very well be productive with out phosphorus fertilizer for a brief interval, in the long term, P fertilizer software or develop applied sciences to recycle P is crucial for sustainable manufacturing just because they’re faraway from the soil-crop system with the yield.Then again, if there’s a demand for potassium and magnesium in a given soil-crop system, present applied sciences on natural agriculture is just not able to offering these two nutrientssustainably. Each these plant vitamins usually are not launched from agricultural soils at a charge thatplants require. Irrigation water and crop residues can provide a portion of those vitamins however the outflow of them as yields is larger than the availability. Normally, crop residues are used for natural manure manufacturing and utilized again to cropping fields with no web achieve.
False impression 4.Nutrient requirement of the crop will be offered by way of natural fertilizers: Nitrogen is probably the most limiting and most responsive nutrient in Sri Lankan agriculture. Normally, annual crops require about 100 kg of N per hectare as available chemical fertilizers. Assuming 75% of nitrogen use effectivity in natural fertilizers and 30% in chemical fertilizers, this equals to about 40 kg of N as natural fertilizers. Though commercially out there compost has solely 1-2% of whole N, if we assume 5% of plant out there N in an natural fertilizer, to fulfill crop N requirement we have to apply 800kg of natural fertilizers per hectare as towards 220 kg of urea. Due to this fact, the practicability and benefits of supplying N from exterior into the cropping fields as natural fertilizers are questionable. Aside from that massive amount, in methods the place natural N administration had been profitable on the planet, Nitrogen has been equipped as a inexperienced manure crop or by introducing a N-fixing legume into the crop rotation. And profitable natural agricultural methods combine animal husbandry as effectively. Introducing a non-food crop into present restricted agricultural lands even for one season in a crop rotation will scale back the meals manufacturing within the nation. The potential for utilizing dry intervals in between the 2 important cropping seasons must be investigated in future analysis. We now have noticed that the lack of rice yield on account of lack of N fertilizer may range from 10% to as excessive as 60%, relying on the soil traits, with a mean lack of about 35%. If nitrogen-rich natural fertilizers can’t be offered to farmers in required portions because of this new coverage determination, yield losses are inevitable.
If we handle Nitrogen requirement by matching Nitrogen requirement of the crop with N availability from natural manures, we’re positive to over apply another vitamins, notably phosphorus and potassium. Accumulation of phosphorus in intensively cultivated vegetable rising soils is already evident and that is partially as a result of software of enormous portions of poultry manure. Extraordinarily excessive phosphorus ranges in these soils (about 10-20 fold) has already polluted floor water our bodies in that space evident as inexperienced coloured water which results in eutrophication. Composition of vitamins in natural manures range extensively and due to this fact extension providers have a frightening process in educating farmers on the suitable charges of natural fertilizer which can be out there in a given space. One of many important challenges in site-specific plant nutrient administration (precision farming) utilizing natural sources,even for scientists, is their inherent variability in nutrient contents and extra importantly nutrient proportions.
False impression 5. Biofertilizers can provide poor plant vitamins in natural solely agricultural methods:One may argue that what is just not offered as natural fertilizers may very well be equipped as bio-fertilizers in natural agricultural methods. Bio-fertilizers comprise micro-organisms that would make plant vitamins out there which can be in any other case not out there; for instance, atmospheric nitrogen fuel byfixation and glued phosphorous in soils by dissolution. Nonetheless, those that have some data on soil microbiology know that microbes that work in a single place don’t essentially work in all areas equally. Solely the fittest will survive in a unique surroundings.Therefore, numerous microbial species/consortiums should be remoted for various soil-crop environments to formulate an efficient biofertilizer. The variety of efficient soil micro-organisms hasindeed been remoted in Sri Lankan laboratories and marketed by some firms.Nonetheless, their effectiveness in several agro-ecosystems and always is questionable. That’s the easy motive why biofertilizershave nonetheless not been authorised by numerous Crop Analysis Institutes as blanket suggestions for a given crop.
There will be many bio-fertilizers or natural fertilizers on the planet that has proven very promising ends in their particular environments. That shouldn’t be a motive for us to import such natural and bio-fertilizers from different nations, as organisms current in such fertilizers may turn into an infinite menace to our soil biodiversity. Testing such fertilizers for his or her environmental security and agronomic effectivenessor even establishing high quality requirements is a frightening process. Due to this fact, additional analysis is required to develop efficient bio-fertilizers for various soil-crop environments in Sri Lanka within the quest for 100% natural fertilizer based mostly agriculture in Sri Lanka.
Options for a sustainable agriculture
It’s prudent that the manufacturing of high-quality natural fertilizers and efficient biofertilizers is a prerequisite to cutdown even a fraction of chemical fertilizers utilized in Sri Lanka. A lot analysis remains to be required to be carried outon natural agriculture to determine probably the most acceptable applied sciences to make agriculture extra environmentally pleasant and sustainable. After which, farmers should be educated on such superior applied sciences. Due to this fact, meticulous planning and a modern applied sciences areessential to realize the anticipated targets from the brand new coverage change. A substantial time frame is thereforerequired to implement methods efficiently,thus recognized.
Nonetheless, as an instantaneous answer for considerations associated to chemical fertilizer, imposing strict laws is a extra practicable and feasiblesolution. Some laws are already out there within the present Fertilizer Act. For indiscriminate use of chemical fertilizers, we have to educate the farmers extra on unwell results associated to such practiceswhile offering incentives/subsidies for farmers who undertake eco-friendly fertilizer applied sciences. A few of such applied sciences are: site-specific nutrient software based mostly on a necessity evaluation donethrough soil or plant testing, use of excellent high quality natural manures and efficient bio-fertilizers to scale back chemical fertilizer utilization, software of chemical fertilizers along with natural matter to retain added vitamins with out being leaked, software of natural matter into already degraded Sri Lankan agricultural lands to extend soil natural matter contents and thereby enhance soil fertility and productiveness. Due to this fact, the current materials subsidy given just for chemical fertilizer needs to be revised to advertise good fertilizer practices amongst farmers.
Potential for urea manufacturing utilizing wastes generated from petroleum refineries, reminiscent of naphtha and atmospheric nitrogen, will be re-investigated. Phosphorus and potassium deposits out there in Sri Lanka needs to be mined correctly and enhance their solubility utilizing environmentallyfriendly applied sciences. Manufacturing of artificial fertilizers inside the nation may push Sri Lanka in direction of a “true” self-sufficiency and save onerous earn international trade for different important functions. Native manufacturing of excellent high quality natural manures and efficient biofertilizers needs to be promoted by offering required technical know-how and monetary assist for entrepreneurs.
Relatively than adopting such possible methods step-by-step, the federal government has banned chemical fertilizer importation in a single day. Thiscould plunge Sri Lanka right into a meals disaster within the coming years on account of decreasing of land productiveness. Due to this fact, the choice to utterly ban chemical fertilizer utilization must be re-considered with none delay. If not, finally it’s the expectations of the 6.9 million individuals who voted for the “Vistas of Prosperity and Splendour”,together with this author, in addition to that of all otherswill be shattered.
The author is a Professor of Soil Fertility and Plant Diet on the College of Agriculture, College of Peradeniya. ([email protected])